I have a project that I had initially setup with Navigator and have since converted over to use BLoC Cubit.
When I use Navigator.of(context).pop(); to go back from a screen that was navigated to using context.read<AppCubits>().pageOneScreen(); I get a black screen instead of being directed back.
Does BloC Cubit's not allow or keep any history like Navigator does?
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I have a back button that would simply call
Navigator.of(context).pop()
and bring the user back to their previous page.
Now with Cubit, using the above doesn't work and returns a blank screen as there is no context stored.
So I have been searching for a solution to this but every one of them seems very verbose, is this type of feature not a part of Cubit or BLoC?
To navigate from page to page currently I am using
context.read<AppCubits>().pageOneScreen();
context.read<AppCubits>().pageTwoScreen();
This works as expected but I am looking for a solution to adding a call that will navigate back to the previous screen/state that was loaded. So if I was on pageTwoScreen, I could click back if I had come from pageOneScreen and have the state changed or at least be directed back to pageOneScreen.
Do I have to create a list and store the state value as a form of rudimentary history and then pop off the previous value and call something akin to
context.read<AppCubits>().historylistvalue()
Related
I have a problem when i navigate to multiple pages and then show search.
More specifically, i have a product page with some details. At the bottom there is a list of similar products.
The flow is:
open many similar products (so I navigate to the same screen using Navigator pushNamed).
then, navigate from the las product page to the search page
tap on search bar, open search delegate using the showSearch function
My issue is that when i tap on the search bar, then the whole widget tree is rebuilded and my app is very heavy because rebuilds the previous product pages and everything else.
This happens due to the general rebuild on keyboard changes(i.e: showing and hiding Keyboard).
I recommend to have a heavy operation like loading data from backend should be held on initState in State with StatefullWidget.
Try to debug and understand why do you rebuild the tree. It seems to me, that you need to simplify a navigation flow.
sorry in advance if i didnt describe my question clearly:
I have several pages made by PageView.builder, while swiping these pages on main screen left and right, I found their initState is already working, and GetXController inside are also loading their data. I use Get.delete<Controller> while clicking back button and coming back to main screen to remove these data.
However, the state and data will bring back to main screen if I didnt activate Get.delete<Controller>, and therefore next time I come to this page, the state of page will be not default, for instance the button still keep pressed status.
So my question is how to prevent page.builder to build the widget before I come inside to this page, or how to delete getxcontroller if I am not in this page. Thanks a lot!
Try resetting the GetX by calling
Get.reset(); --> this will re-initialize controllers
Alternatively calling
Get.put(ControllerName()); in a build method will re-initialize the controller
I have a problem with my Here Maps Navigation. I can start the navigation on my flutter app but every time I open another page on the app and come back to the navigation page, it restarts the navigation. It tries to get the current location again, takes a lot of time to do that, and shows the default "invalid" map page. I want the navigation to save it's current state even if I change the view to another page on my app and come back to navigating. Is there a way to do this? Am I missing something here?
I finally found a way to solve it by saving the state of my Flutter pages. I used the PageView widget for the main.dart's scaffold body and AutomaticKeepAliveClientMixin on the pages I wanted to save the states of. You can check this YouTube video for how to implement this: https://www.youtube.com/watch?v=fGe45NikVqE
Is there anyway to check route name of last screen after pop? When application start and land on home screen, there are several widgets like view profile, product carousel and so on.
Scenario: User navigate into product listing page, then detail page, click purchase and perform actions. After user purchased, shows purchased successful screen, call Navigator.of(context).popUntil(routeName) back to home screen.
What I want to achieve: After land in home screen, programmatically call api to refresh my balance. Route Observer able to detect navigation back to home screen with didPopNext() method. But this is called no matter it pop from which screen. Therefore the api will repeatedly called which is not ideal. How do I know it was pop from purchased successful screen instead of product listing screen?
Grateful on any helps and hints!
If you where using pop() then you have an option to return some data to previous route but since you are using popUntil() you won't be able to do this. So I think you should clear every route and push home route again from purchased successful page using either pushAndRemoveUntil() or pushNamedAndRemoveUntil(). That means you can now pass an argument to home screen by which you can decide whether to call the API or not.
Navigator.of(context).pushNamedAndRemoveUntil(
'/',
(Route<dynamic> route) => false,
arguments: []
);
Another option would be to figure out a way to return data using popUntil(), Something like this, maybe?
I'm looking for a way to intercept navigation back conditionally.
User/server can modify global state of the app like authentication, causing page to navigate to login form, but when user navigates to screen A then presses back button twice, user is still able to see widgets that are supposed to be available only for logged in session.
I've tried all I could thought of:
onGenerateRoute in MaterialApp but it's not triggered when back button is pressed
WillPop is a solution to that, but all top-level widgets would have to be wrapped in it and I need to remember to pass auth state to all the widgets, it's not really scalable solution, but could work
navigatorObservers is notified about Navigator.pop events seems not to be able to prevent navigation
Ideally, would like to avoid 3rd party dependencies with hooks on every widget like back_button_interceptor.
It should also work with statelesswidgets, where dispose() method is not available.
Is there any way to get something like single class/point of failure "navigator interceptor" which would return true/false and be able to modify route in flight based on a condition?
Looking into the implementation of WillPopScope, it makes use of the addScopedWillPopCallback() function of the ModalRoute.
https://api.flutter.dev/flutter/widgets/ModalRoute/addScopedWillPopCallback.html
If you implemented a router with onGenerateRoute it should be possible to add an universal check for every route you push. Maybe you could even make a customized Route class inherited from MaterialPageRoute that includes that logic.
If i understood your problem right,i feel like intercepting back navigation is the wrong approach. I would rather try to remove the unauthorized pages from the navigation stack when navigating back to the login screen with Navigator.pushNamedAndRemoveUntil()